High mammographic breast density (MBD) reduces the sensitivity of mammography for early detection of breast cancer (BC), and is a strong predictor of BC risk. To date, 24 states, including New York, have passed legislations mandating that all women with high MBD receive written notification that informs them about the lower sensitivity of mammography and higher BC risk associated with dense breasts, and advises them to consult their physicians about risk assessment and screening; > 40% of U.S. women fall into categories of high MBD that require this notification. The legislation may worsen breast cancer health disparities, as: 1) any benefits gained from the law rests on individual women's actions and minority and low socioeconomic status women with more limited resources (e.g., less education, health insurance coverage, and coping resources) may be less able to understand and act on this information, and 2) the law does not provide for additional financial or clinical support for women with high MBD. Thus, the law may prove less beneficial in promoting BC screening in minority and low socioeconomic women, and may ultimately exacerbate disparities in BC early detection and survival. We propose a prospective study to examine the impact of breast density notification on psychological responses and subsequent screening behaviors of a racially and socioeconomically diverse study population. Drawing on our large and diverse screening patient population in Upper Manhattan, we will collect interview data on relevant constructs, informed by the Protection Motivation Theory, from 1000 women, aged 40-60 years, at the time of clinical mammography visits (baseline), and at 1-month and 12-months post- baseline. Separately, we will use electronic health records to monitor the use of subsequent mammography and supplemental breast imaging tests in the study population for up to 30 months following baseline. Defining MBD notification status as women with high MBD who receive breast density notification vs. women with low MBD who do not receive breast density notification, the aims of this study are to 1) Examine the associations of MBD notification status with general and breast cancer-specific psychological outcomes (e.g., worry, anxiety, perceived risk, response efficacy), and information seeking behavior at baseline, and at 1 month and 12 months post baseline; 2) Examine the associations of MBD notification status with participation in subsequent mammography and in supplemental imaging screening (breast ultrasound, MRI) within 30 months of the baseline; 3) Examine differences in the associations of MBD notification status with psychological outcomes, information seeking behavior and breast cancer screening behavior by race/ethnicity and educational attainment. This research will provide essential and timely data on how legislative actions that increase disclosure of clinically relevant data can affect population level cancer prevention and health disparities, and will inform future intervention planning and clinical delivery of personal breast density data in low socioeconomic and racially minority patient populations.